In Realtime-Live Testing, we have added Zoom button in the left-sided ToolBar to enlarge the iOS device together with zoomed text to make the text easily readable inside the device 
here you could
zoom out with '+'
zoom in (to normal size) with '-'
and reset to normal size(after zoom out) with 'Reset’
Attaching a screenshot for quick help!
I Hope this zoom functionality with the new Zoom feature would be definitely helpful for smooth iOS-device testing over the platform.
Thank you 
Happy Testing! 
for Testers